Recent evidence suggests that Sydenham chorea, obsessive/compulsive disorder and Tourette syndrome may have a similar autoimmune basis. Dr. Zabriskie and co-workers have shown that a specific B-cell D8/17 clonal marker is greatly expanded in all of these groups. The goal of the present study is to correlate brain autoantigens, B-cell clonal status and neurologic, psychaitric and cognitive outcome in all of these groups. If correlations are found, efforts will be made to isolate the respective autoantigens.